Page turning facility

ABSTRACT

A device for storing information electronically and which has a pen-sensitive screen enabling a user to make freehand input has the screen divided into two areas--a main area and a subsidiary area adjacent the main area. 
     The user can tag items of freehand input causing a tag item to be displayed alongside the freehand input and can subsequently manipulate (eg delete, move, copy) the freehand input by selecting and manipulating the associated tag item. 
     Tag items provide a permanent way of structuring data and are an elegant way of uniting several data manipulations.

TECHNICAL FIELD

The present invention relates to devices for displaying pages ofelectronically stored information. The present invention relatesparticularly, but not exclusively, to handheld computer devices with apen/stylus for user input and a relatively small display screen.

BACKGROUND ART

Known pen-based handheld devices for displaying pages of electronicallystored information have used a variety of ways to facilitate pageturning. One of these, the Amstrad `PenPad`, has a small screen withforward and backward facing arrows displayed next to the screen. Theuser can turn pages in the desired direction by touching the arrows.Holding the pen down achieves a constant predetermined page turning rateallowing the user to `riffle` rapidly through pages in succession,although without being able to control the page turning rate.

Another known device is the Sharp `Action Manager` which is anotherpen-based handheld device in which pages are displayed with turned upcorners. On tapping such a corner with the pen, the page turns. There isno mechanism for riffling rapidly through pages.

Neither of these devices provides a naturalistic page turning facility.

Many word processing packages support a vertical scroll bar whichscrolls through pages of electronically stored information as if theywere attached top to bottom and this is also the approach used in theTandy `Zoomer` which is another pen-based handheld device. Thedisadvantage of this approach is that the scroll bar takes up screenspace, which is a particular disadvantage for small screen devices. Ifthere is no scroll block, the scroll facility is tantamount to a pair ofarrows similar to the arrangement in the Amstrad PenPad.

DISCLOSURE OF INVENTION

According to the present invention we provide a device for displayingpages of electronically stored information comprising a pen/fingersensitive symbol enabling a user to browse the information by pageturning wherein the symbol has page delimiters and the device isconfigured so that traversal of a page delimiter causes a predeterminednumber of pages to be turned.

The provision of page delimiters has the advantage of allowing the usergreater control over page turning. The user can stroke the symbolrepeatedly to riffle through pages and the rate of page turning is underdirect user control. In order to make best use of limited screen size ina handheld device, the symbol is situated outside the active area of thedisplay screen of the device.

Preferably, the predetermined number of pages is one so that a singlepage is turned on traversal of each page delimiter.

Preferably, traversal of a page delimiter causes tactile feedback to beprovided to the user. For example, in a pen-based device the pagedelimiters may be ridges or indentations so that these can be felt bythe user when traversed by the pen.

In the embodiment to be described, the symbol depicts an open book.Preferably, there is an arrow overlaying the book symbol. This arrowinforms novice users of the function of the open book symbol.

In order to make best use of limited screen size in a handheld device,the symbol is situated beside, rather than on, a display screen of thedevice.

Alternatively, means are provided enabling a user to select a positionrelative to the symbol so as to cause a page at a corresponding positionin the sequence of stored electronic information to be displayed.

BRIEF DESCRIPTION OF DRAWINGS

A particular embodiment of the present invention will now be described,by way of example, with reference to the accompanying drawings in which:

FIG. 1 is a diagram of a device according to the present invention;

FIG. 2 shows a symbol depicting an open book.

BEST MODE FOR CARRYING OUT THE INVENTION & INDUSTRIAL APPLICABILITY

FIG. 1 depicts a pen-based handheld device 10 for storing and displayingpages of electronic information comprising a display screen 12 and a pen14 for user input. The device 10 also comprises buttons 16 for variousfunctions (not relevant to the present invention) and a book symbol 18for enabling users to browse pages of stored information.

FIG. 2 shows the symbol 18 in more detail. The symbol 18 is attached tothe casing of the device 10. Electro-magnetic sensors (not shown) arepositioned within the casing and are spaced around the casing so as tosense movement of the pen on the screen 12 and on the off-screen buttons16. An alternative to electromagnetic sensors would be pressure sensors.

The symbol 18 is notionally divided into three segments 20, 21 and 22,the boundaries between which are indicated by dotted lines in FIG. 2.The symbol 18 includes a representation 24 of an open book and adouble-headed arrow 26. The left hand head 28 of the arrow 26 is in theregion 20 and the right hand head 30 of the arrow is in the region 22.The book representation 24 and the body 34 of the arrow 26 are in theregion 21. The software which handles data representing the signals fromthe pen sensors divides the symbol into the three regions 20, 21 and 22.

The book representation 24 comprises page delimiters 36 which are ridgesformed in the symbol 18 which the user can feel as the pen 14 is movedover the symbol 18.

In use, as the user moves the pen 14 along the body 34 of the arrow, orindeed anywhere within the region 21, successive pages of storedinformation are displayed, depending on the direction of movement alongthe arrow body 34. As a page delimiter 36 is traversed by the pen 14,the next page in the direction of movement of the pen 14 is displayed.If the user taps one of the arrow heads 28 or 30, this causes the device10 to display the next page in the direction indicated by the tappedarrow head. The device is configured so that a single tap anywhere inthe regions 20 or 22 is interpreted as a tap on the respective arrowhead 28 or 30.

In order to riffle through a large number of pages of storedinformation, the user repeatedly moves the pen 14 in a single directionin the region 21 over the body 34 of the arrow 26.

An example pseudo-code implementation of the above-described embodimentis as follows:

    __________________________________________________________________________    State myState;  /* one of: OVER.sub.-- LEFT.sub.-- ARROW.sub.-- HEAD,    OVER.sub.-- RIGHT.sub.-- ARROW.sub.-- HEAD, OVER.sub.-- ARROW.sub.-- BODY    */    Position myLastPosition;  /* Last recorded position when rippling */    When.sub.-- pen.sub.-- down.sub.-- over.sub.-- book.sub.-- icon(position){    if(over.sub.-- left.sub.-- arrow.sub.-- head(position))    myState = OVER.sub.-- LEFT.sub.-- ARROW.sub.-- HEAD;    if(over.sub.-- right.sub.-- arrow.sub.-- head(position))    myState = OVER.sub.-- RIGHT.sub.-- ARROW.sub.-- HEAD;    if(over.sub.-- arrow.sub.-- body(position)){    myState = OVER.sub.-- ARROW.sub.-- BODY;    }    myLastPosition = position;    book.sub.-- icon.sub.-- grab.sub.-- pen.sub.-- focus( ); /* send future    pen events to routines below . . . */    }    When.sub.-- pen.sub.-- dragged.sub.-- and.sub.-- book.sub.-- icon.sub.--    has.sub.-- focus(position){    /* Check whether user has moved onto arrow body from LEFT or RIGHT    arrowheads */    if((myState == OVER.sub.-- LEFT.sub.-- ARROW.sub.-- HEAD) or (mysState.    ==    OVER.sub.-- RIGHT.sub.-- ARROW.sub.-- HEAD)){    if(over.sub.-- arrow.sub.-- body(position)) mystate = OVER.sub.--    ARROW.sub.-- BODY;    }    if(myState == OVER.sub.-- ARROW.sub.-- BODY){    intpages = page.sub.-- edges.sub.-- crossed(position, myLastPosition));    if(pages <0 or pages >0) do.sub.-- ripple(pages);    myLastPosition = position;    }    }    When.sub.-- pen.sub.-- is.sub.-- raised.sub.-- and.sub.-- book.sub.--    icon.sub.-- has.sub.-- focus(position){    if(myState == OVER.sub.-- LEFT.sub.-- ARROW.sub.-- HEAD) turn.sub.--    back.sub.-- one.sub.-- page( );    if(myState == OVER.sub.-- RIGHT.sub.-- ARROW.sub.-- HEAD) turn.sub.--    forward.sub.-- one.sub.-- page( );    release.sub.-- pen.sub.-- focus( );    }    __________________________________________________________________________

In the code example above, the symbol 18 is sensed as a rectangularregion subdivided into the three smaller rectangular regions 20, 21 and22 representing (LEFT₋₋ ARROW₋₋ HEAD.linevert split.ARROW₋₋BODY.linevert split.RIGHT₋₋ ARROW₋₋ HEAD).

The device 10 may be configured so that pages are riffled in one-to-onecorrespondence with page delimiters being traversed. Alternatively,successive pages may be displayed when the pen 14 is moved apredetermined distance along the arrow body 34. In this way a variablescaling factor can be used for riffling through pages of electronicallystored information. The scaling factor may vary automatically accordingto the number of pages stored.

The above-described embodiment allows riffling to continue even if thepen 14 is dragged outside the region 21 of the symbol 18. The movementof the pen can still be sensed in the region just outside the symbol 18.

A further modification is for the user to be able to jump to a positionin the collection of stored pages by tapping the pen 14 (or using someother defined gesture) on the corresponding part of the bookrepresentation 34. In other words, if the pen is tapped over the arrowbody it may turn the book to a page corresponding to that percentage ofthe distance through the book. For example, by tapping the pen 14 on themiddle of the book representation 34, the device 10 causes the page inthe middle of the collection of stored pages to be displayed. In thiscase pages need only be turned in response to a pen-up movement over thebook-icon. Pseudo-code for implementing this modification is as follows:

    ______________________________________    When.sub.-- pen.sub.-- up.sub.-- over.sub.-- book.sub.-- icon(position){     if(over.sub.-- left.sub.-- arrow.sub.-- head)position))      turn.sub.-- back.sub.-- one.sub.-- page( );     if(over.sub.-- right.sub.-- arrow.sub.-- head(position))      turn.sub.-- forward.sub.-- one.sub.-- page;     if(over.sub.-- arrow.sub.-- body(position)){      offset = distance.sub.-- from.sub.-- left.sub.-- edge.sub.-- of.sub.--    arrow.sub.-- body(position);      page = offset * total.sub.-- number.sub.-- of.sub.-- pages( )/      ARROW.sub.-- BODY.sub.-- WIDTH;      turn.sub.-- to.sub.-- page(page)     }    ______________________________________

Although it is desirable in a small-screen device not to clutter thescreen with icons, the symbol 18 could be implemented as an on-screenicon if desired.

The symbol 18 is positioned off-screen so as not to clutter the screenwith icons. In some devices, the screen may have a marginal, non-activearea and the symbol may be positioned there rather than on the devicecasing.

I claim:
 1. A device for displaying pages of electronically storedinformation comprising a static symbol situated outside the activedisplay area for enabling a user to browse the information in a pageturning mode, wherein the symbol has a plurality of page delimiters, thedevice being configured so that traversal of each page delimiter causesa predetermined number of pages to be turned.
 2. A device according toclaim 1 wherein the predetermined number is one.
 3. A device accordingto claim 1 wherein traversal of a page delimiter causes tactile feedbackto be provided to the user.
 4. A device according to claim 3 wherein thepage delimiters are ridges.
 5. A device according to claim 3 wherein thepage delimiters are indentations.
 6. A device according to claim 1wherein the symbol depicts an open book.
 7. A device according to claim1 wherein the symbol is situated beside a display screen of the device.8. A device according to claim 1 comprising means enabling a user toselect a position relative to the symbol so as to cause a page at acorresponding position in the sequence of stored electronic informationto be displayed.
 9. A device according to claim 2 wherein traversal of apage delimiter causes tactile feedback to be provided to the user.
 10. Adevice according to claim 2 wherein the symbol depicts an open book. 11.A device according to claim 3 wherein the symbol depicts an open book.12. A device according to claim 4 wherein the symbol depicts an openbook.
 13. A device according to claim 5 wherein the symbol depicts anopen book.
 14. A device according to claim 2 wherein the symbol issituated beside a display screen of the device.
 15. A device accordingto claim 3 wherein the symbol is situated beside a display screen of thedevice.
 16. A device according to claim 4 wherein the symbol is situatedbeside a display screen of the device.
 17. A device according to claim 5wherein the symbol is situated beside a display screen of the device.18. A device according to claim 6 wherein the symbol is situated besidea display screen of the device.
 19. A device according to claim 2comprising means enabling a user to select a position relative to thesymbol so as to cause a page at a corresponding position in the sequenceof stored electronic information to be displayed.
 20. A device accordingto claim 3 comprising means enabling a user to select a positionrelative to the symbol so as to cause a page at a corresponding positionin the sequence of stored electronic information to be displayed.
 21. Adevice according to claim 4 comprising means enabling a user to select aposition relative to the symbol so as to cause a page at a correspondingposition in the sequence of stored electronic information to bedisplayed.
 22. A device according to claim 5 comprising means enabling auser to select a position relative to the symbol so as to cause a pageat a corresponding position in the sequence of stored electronicinformation to be displayed.
 23. A device according to claim 6comprising means enabling a user to select a position relative to thesymbol so as to cause a page at a corresponding position in the sequenceof stored electronic information to be displayed.
 24. A device accordingto claim 7 comprising means enabling a user to select a positionrelative to the symbol so as to cause a page at a corresponding positionin the sequence of stored electronic information to be displayed.